1. Field of the Invention
The present invention generally relates to a compact heat disinfection unit for contact lenses and, more specifically, to a compact heat disinfection unit for contact lenses with additional safety features which utilizes low heat levels, a retractable blade assembly, and a separate dual compartment lens case to contain the solution and lenses.
2. Description of the Prior Art
In the past, the need to periodically clean and store contact lenses has been well known. This need was met by a variety of contact lens disinfection units. For example, Bowen, U.S. Pat. No. 4,578,566, discloses a contact lens disinfecting unit comprising a plastic housing, compartments for the lenses within the plastic housing, an electrically energized heating means, and electrical circuitry to connect the heating means to the energizing source. Subsequently, however, a need was felt for contact lens disinfection units which are suitable for portable use. Attempts to meet this need resulted in Braun, U.S. Pat. No. 4,701,597. Braun discloses a contact lens disinfection which comprises chambers for the lenses, a heating element, heat sinks coupled to the heating elements and the chambers, a thermostat, a thermostat heat sink, and a heat transfer element for transferring a controlled amount of heat from the heating element to the thermostat heat sink.
Despite the compact size of the lens disinfection units, problems with their use still existed. For example, the design of the units such as in Braun encouraged users to place the lens case on top of the unit and pour saline solution directly into the lens compartment while the unit was plugged into an electrical outlet. This created problems of saline solution spilling over from the lens case onto the unit and causing short-circuiting within the unit. In U.S. Pat. No. 4,873,424, another attempt to solve these prior art problems was disclosed. However, the Ryder device would allow a user to place a lens case on top of the unit to pour solution therein, allowing the same to possibly enter inside the unit. Also, there are no foldable contacts or hinged blades in Ryder allowing compact storing and travel. The Ryder unit requires one to plug it into the wall (which turns it on), then grasp the unit with wet hands (conventional cleaning of contacts involves washing of the lens in one's hands which results in wet hands) which might result in water and/or saline solution short-circuiting the device of the wall outlet. Further, in Ryder, there is nothing holding or bracing the case B inside the unit and centering the same therein for uniform heating.
Prior compact lens disinfection units that are suitable for traveling purposes generally have protruding parts, such as the blade assembly which can catch on clothing or the like. That is, prior art units are comprised of several loose parts, and require a non-folding electrical plug which tends to catch on other items in the user's luggage. Therefore, a need exists for a compact disinfection unit with additional safety features which are suitable for convenient traveling purposes.